A biochemist monitors the relationship between the concentration of a specific catalyst, ccc mmol/L, and the resulting reaction rate, rrr μ\muμmol/s, for 10 distinct chemical trials. The experimental results are summarized as follows:
∑c2=9625∑cr=6792.5∑c=275∑r=220Srr=325 \sum c^2 = 9625 \quad \sum cr = 6792.5 \quad \sum c = 275 \quad \sum r = 220 \quad S_{rr} = 325 ∑c2=9625∑cr=6792.5∑c=275∑r=220Srr=325Determine the values of SccS_{cc}Scc and ScrS_{cr}Scr for this experiment.
Calculate, to 3 significant figures, the product moment correlation coefficient (PMCC) between ccc and rrr.
Find the equation of the least squares regression line of rrr on ccc in the form r=a+bcr = a + bcr=a+bc.
Identify which of the two variables is the explanatory variable in this study, providing a reason for your choice.
Using your regression model, estimate: (i) the reaction rate when the concentration of the catalyst is 32 mmol/L, (ii) the total change in the reaction rate for an 8 mmol/L increase in concentration.
It was later found that one trial, where the concentration was 20 mmol/L and the reaction rate was 25 μ\muμmol/s, was incorrectly transcribed and is considered an outlier.
State, with a reason, the effect that removing this outlier would have on the value of the PMCC.
278 exam-style questions on CCEA A Level Maths 2.5 Data presentation and interpretation, covering 2.5.1 Data presentation and interpretation, 2.5.2 Data presentation and interpretation, 2.5.3 Data presentation and interpretation, 2.5.4 Data presentation and interpretation, 2.5.5 Data presentation and interpretation, 2.5.6 Data presentation and interpretation, 2.5.7 Data presentation and interpretation, 2.5.8 Data presentation and interpretation, 2.5.9 Data presentation and interpretation, and 2.5 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.